Avaliação de diferentes substratos na aclimatização de plântulas de Epidendrum ibaguense (Kunth).

O objetivo deste trabalho foi avaliar diferentes substratos na aclimatização de plântulas micropropagadas de orquídeas da espécie Epidendrum ibaguense

High Trypanosoma spp. diversity is maintained by bats and triatomines in Espírito Santo state, Brazil

The aim of this study was to reevaluate the ecology of an area in the Atlantic Forest, southeast Brazil, where Chagas disease (CD) has been found to occur. In a previous study, immediately after the occurrence of a CD case, we did not observe any sylvatic small mammals or dogs with Trypanosoma cruzi cruzi infections, but Triatoma vitticeps presented high T. c. cruzi infection rates. In this study, we investigated bats together with non-volant mammals, dogs, and triatomines to explore other possible T. c. cruzi reservoirs/hosts in the area. Seventy-three non-volant mammals and 186 bats were captured at three sites within the Guarapari municipality, Espírito Santo state. Rio da Prata and Amarelos sites exhibited greater richness in terms of non-volant mammals and bats species, respectively. The marsupial Metachirus nudicaudatus, the rodent Trinomys paratus, and the bats Artibeus lituratus and Carollia perspicillata were the most frequently captured species. As determined by positive hemocultures, only two non-volant mammals were found to be infected by Trypanosoma species: Monodelphis americana, which was infected by T. cascavelli, T. dionisii and Trypanosoma sp., and Callithrix geoffroyi, which was infected by T. minasense. Bats presented T. c. cruzi TcI and TcIII/V, T. c. marinkellei, T. dionisii, T. rangeli B and D, and Trypanosoma sp. infections. Seven dogs were infected with T. cruzi based only on serological exams. The triatomines T. vitticeps and Panstrongylus geniculatus were found to be infected by trypanosomes via microscopy. According to molecular characterization, T. vitticeps specimens were infected with T. c. cruzi TcI, TcII, TcIII/V, and TcIV, T. c. marinkellei and T. dionisii. We observed high trypanosome diversity in a small and fragmented region of the Atlantic Forest. This diversity was primarily maintained by bats and T. vitticeps. Our findings show that the host specificity of the Trypanosoma genus should be thoroughly reviewed. In addition, our data show that CD cases can occur without an enzootic cycle near residential areas

Testing the recovery of stellar rotation signals from Kepler light curves using a blind hare-and-hounds exercise

We present the results of a blind exercise to test the recoverability of stellar rotation and differential rotation in Kepler light curves. The simulated light curves lasted 1000 days and included activity cycles, Sun-like butterfly patterns, differential rotation and spot evolution. The range of rotation periods, activity levels and spot lifetime were chosen to be representative of the Kepler data of solar like stars. Of the 1000 simulated light curves, 770 were injected into actual quiescent Kepler light curves to simulate Kepler noise. The test also included five 1000-day segments of the Sun's total irradiance variations at different points in the Sun's activity cycle. Five teams took part in the blind exercise, plus two teams who participated after the content of the light curves had been released. The methods used included Lomb-Scargle periodograms and variants thereof, auto-correlation function, and wavelet-based analyses, plus spot modelling to search for differential rotation. The results show that the `overall' period is well recovered for stars exhibiting low and moderate activity levels. Most teams reported values within 10% of the true value in 70% of the cases. There was, however, little correlation between the reported and simulated values of the differential rotation shear, suggesting that differential rotation studies based on full-disk light curves alone need to be treated with caution, at least for solar-type stars. The simulated light curves and associated parameters are available online for the community to test their own methods.Comment: Accepted for publication in MNRAS. Accepted, 13 April 2015. Received, 26 March 2015; in original form, 9 November 201

On the chromospheric activity of stars with planets

Context. Signatures of chromospheric activity enhancement have been found for a dozen stars, pointing to a possible star-planet interaction. Nevertheless in the coronal activity regime, there is no conclusive observational evidence for such an interaction. Does star-planet interaction manifest itself only for a few particular cases, without having a major effect on stars with planets in general? Aims. We aim to add additional observational constraints to support or reject the major effects of star-planet interactions in stellar activity, based on CaII chromospheric emission flux. Methods. We performed a statistical analysis of CaII emission flux of stars with planets, as well as a comparison between CaII and X-ray emission fluxes, searching for dependencies on planetary parameters. Results. In the present sample of stars with planets, there are no significant correlations between chromospheric activity indicator log(R'HK) and planetary parameters. Further, the distribution of the chromospheric activity indicator for stars without planets is not distinguishable from the one with planets.Comment: 6 pages, 5 figures, submitted to A&

Desinfestação de explantes radiculares de bacurizeiro (Platonia insignis Mart.).

O bacurizeiro (Platonia insignis Mart.) é uma planta frutífera que apresenta madeira com boa característica físico-mecânica e suas sementes podem ser utilizadas para extração de óleo. Este trabalho objetivou avaliar diferentes tratamentos de desinfestação de explantes radiculares de bacurizeiro para o seu estabelecimento in vitro. Segmentos radiculares foram lavados com água destilada e detergente, em seguida foram seccionados em estacas de 1,5 a 2,0 cm, as quais foram imersas em álcool 70% (v/v) por 1 minuto e em soluções de hipoclorito de sódio a 0,50, 1,25 e 1,75% (p/v), durante 20 e 30 minutos. Metade das estacas foram imersas em solução antifúngica (carboxin 0,067% p/v + thiram 0,067% p/v, carbendazim 0,17% p/v, clorotalonil 0,17% p/v + tiofanato-metílico 0,067% p/v) por 30 minutos, em seguida todos explantes ficaram imersos em solução antioxidante com 100 mg.L-1 de ácido ascórbico e 150 mg.L-1 de ácido cítrico por 10 minutos. Os explantes foram inoculados em meio MS acrescido de 3,0% de sacarose, 100 mg/L de cefotaxima e 0,8% de ágar. Foram utilizadas dez repetições por tratamento. Observou-se que a imersão em solução de hipoclorito de sódio a 1,75% por 30 minutos, foi eficiente quando associada à utilização da solução antifúngica, obtendo descontaminação total dos explantes. As soluções de 0,50 e 1,25%, mesmo associadas à solução fungicida, resultaram em níveis de contaminação variáveis. Os tratamentos nos quais não se utilizou solução antifúngica atingiram 100% de contaminação